本研究透過文獻回顧，了解拍撲時翼面設計及動作對空氣動力學的影響，欲以仿獨角仙拍撲機構探討不同鞘翅與後翼夾角之翼面交互作用。動作分析實驗結果顯示，影響本實驗機構垂直力的主要因素為延遲失速效應和質量附加效應。延遲失速效應由旋轉座標系向心力引起的展向流所致，並隨翼面迎風角度與環境流場而變化，而質量附加效應則由拍撲角加速度主導。力量測實驗結果顯示，仿獨角仙機構在0.24週期及0.71週期時垂直力達極值，並隨材料及鞘翅與後翼間夾角不同而變化。TPU翼膜因彎曲模量小，其垂直力最大且拍撲平面傾斜角最接近真實獨角仙。
基於前述結果，本研究針對TPU翼膜在0.24週期及0.71週期時進行力量測實驗及PIV流場觀測。實驗發現，在0.24週期時，鞘翅能提升垂直力，且鞘翅與後翼夾角為25°時效果最高，而無鞘翅時垂直力最低，原因是鞘翅翼後緣渦流增大後翼翼前緣渦流，提升延遲失速效應。而在0.71週期時，鞘翅會降低垂直力，且鞘翅與後翼夾角為25°時垂直力最低，而無鞘翅時垂直力最高，原因是鞘翅翼後緣渦流的產生反而破壞後翼翼表面邊界層，減少了後翼的垂直力。而造成鞘翅拍撲對後翼上下拍時垂直力有不同影響的原因為鞘翅形狀及後翼旋轉角。此外，流場觀測未能顯示鞘翅展向流剝離現象，因鞘翅拍撲角速度較低，難以達到展向流剝離。
本研究確定了不同鞘翅與後翼夾角下翼面交互作用的關鍵因素，為未來相關機構設計及實驗提供實驗依據及參考。

This study investigates the impact of wing interaction effects of different angles between elytron and hindwing using a beetle-like flapping mechanism. Previous literatures indicate that the primary factors affecting the vertical force in this experimental mechanism are the absence of stall and added mass effect. Force measurement experiment results show that the vertical force of the beetle-mimicking mechanism reaches its peak at 0.24 and 0.71 periods and varies with different materials and the angle between the elytron and hindwing. Due to its low flexural modulus, the TPU wing membrane exhibits the highest vertical force and a stroke plane angle closest to that of a real beetle.
Based on the aforementioned results, this research conducted force measurement experiments and Particle Image Velocimetry on the TPU wing membrane at 0.24 and 0.71 period. The experiments revealed that at 0.24 period, the elytron enhance the vertical force, with the maximum effect occurring at an angle of 25° between the elytron and hindwing. The vertical force is the lowest without the elytron, as the vortices at the trailing edge of the elytron increase the vortices at the leading edge of the hindwing, enhancing the absence of stall effect. Conversely, at 0.71 period, the elytron reduces the vertical force, with the lowest vertical force occurring at a 25° angle between the elytron and hindwing, while the highest vertical force is observed without the elytron. This is because the vortices generated at the trailing edge of the elytron disrupt the boundary layer on the surface of the hindwing, reducing their vertical force. The different impacts on the vertical force during the upstroke and downstroke of the hindwing are attributed to the shape of the elytron and the rotation angle of the hindwing. Furthermore, the flow field observations did not show any spanwise flow separation of the elytron, as the flapping angular velocity of the elytron is relatively low, making it difficult to achieve spanwise flow separation.
This research identifies the key factors in the interaction between wing surfaces at different angles between the elytron and hindwing, providing an experimental basis and reference for future related mechanism design and experiments.

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